78901997 has 2 divisors, whose sum is σ = 78901998. Its totient is φ = 78901996.

The previous prime is 78901967. The next prime is 78902051. The reversal of 78901997 is 79910987.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 76143076 + 2758921 = 8726^2 + 1661^2 .

It is a cyclic number.

It is not a de Polignac number, because 78901997 - 2¹⁴ = 78885613 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (78901967) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 39450998 + 39450999.

It is an arithmetic number, because the mean of its divisors is an integer number (39450999).

Almost surely, 2^78901997 is an apocalyptic number.

It is an amenable number.

78901997 is a deficient number, since it is larger than the sum of its proper divisors (1).

78901997 is an equidigital number, since it uses as much as digits as its factorization.

78901997 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 285768, while the sum is 50.

The square root of 78901997 is about 8882.6796069655. The cubic root of 78901997 is about 428.9065366927.

The spelling of 78901997 in words is "seventy-eight million, nine hundred one thousand, nine hundred ninety-seven".